1. during a threesome involving one man and two women. the women are stacked stomach too back and the man assumes a kneeling position behind them and proceeds to push his penis from one girl to the next, starting with the bottom girl working his way up. Or reverse the order and direction for variations.

The highlight of my threesome was when i pulled the escalator on the two of them. Next time I think I'm gonna add another floor!

The Escalator is an act of sexual prowess. It is also form of The Bulldozer where you run the girl up and down a set of stairs until she cooperates, and does what she is told. This is the ultimate demeaning act of sex that you can do to your partner. Just be warned, going up the stairs is a lot harder than you may think. So be a gentleman and buy that bitch some knee pads.

Suzie: "Where did you get all those bruises from?"
Dana: "I got them last night, Jon wanted to try The Escalator out."